Roof construction



Aug. 11, 1953 w. SWIRES 2,648,132

' ROOF CONSTRUCTION Filed Nov. 5, 1951 3 Sheets-Sheet l 27 FIG. 3. in

WILL/AM SM'RES Aug. 11, 1953 w. SWIRES 2,648,132

ROOF CONSTRUCTION Filed Nov. 5, 1951 5 Sheets-Sheet 2 FIG. 5.

Inventor WILLIAM SW/RES y W mvm Aug.1l,l953 WSWIRES 2,6 8 132 ROOF CONSTRUCTION Filed Nov. 5, 1951 v s Sheets-Sheet 5 Immfa WILL/AM s wine's c z Attorney Patented Aug. 11, 1953 ROOF CONSTRUCTION William Swires; Helsby, near Warrington, England ApplicationNovember 5, 1951, Serial No. 254,825 InGreat Britain November 1950.

5 Claims. 1,

The present invention relates to timbered': roof construction and has an object to provide an improved method of, and apparatus for markin'g-ofi the various roof timbers prior to cutting.

In the construction of timbered roofs; the angles of inclination of the various rafters and spars and associated purlins are inter-related and governed by the rise and span of the roof and it is customary to determine the required angle for each roof member prior to cutting to the desired length.

According to the present invention the angles of the different roof members are predetermined according to the pitch of the roof by means of an apparatus in which adjustment of one adjustable member' to correspond with the pitch of the roof causes a plurality of associated members to assume the angles necessary for cutting the various roof members so that once the apparatus has been set, it may be used for marking off lengths of timber to form the various roof members.

The invention is particularly though not exclusively adaptable for the construction of hip roofs and will now be described, by way of example, with relation to the construction of a hip roof. In the following description reference is made to the accompanying drawings, whereon:

Figure 1 is a fragmentary perspective view of the timbers forming the frame construction of a hip roof.

Figure 2 is a perspective detail view of one of the hip rafters;

Figure 3 is a perspective view of one end of one of the purlins;

Figure 4 is a perspective view of one of the jack rafters or spars;

Figure 5 is a plan view of the marking-off instrument or apparatus, and,

Figures 6 to 14 inclusive are fragmentary diagrams illustrating the manner in which the instrument shown in Figure 5 is used to mark-off the various timbers or roof members for cutting.

Referring to Figure 1, the roof comprises the hip rafters 20, purlins 2| and jack rafters or spars 22. The hip rafters have a top out 23, a plumb cut 24 and a foot cut 25. The purlins have a top out 25, a plumb cut 21 and a lip cut 28. Similarly, the jack rafters or spars have a top out 29, a plumb cut and a foot cut 3|. All the cuts just referred to have to be markedoff on the various timbers and this is greatly facilitated by the use of the instrument now to be described.

Referring to Figure 5, the instrument comprises a U-shaped frame 3.2 having a long leg 33' and a short leg. 34. Pivotally mounted towards the extremity of the short leg 34, as indicated at 35, is an elongated base member or fence 36 having straight-edges 3! and 38 adapted to be brought into register with a longitudinal surface of the timber to be. marked-off. The end of the base member 36, remote from the pivot 35, is provided with a clamping screw 39 slidable in an arcuate slot 40 in the long leg 33 of the frame. The slot 411 is associated with a scale 41 of angles of inclination for different roofs; By slackening the clamping screw 39 the base member 35 can be moved about its pivot 35 and set against any one of the graduations of the scale 4! and then secure at this setting by tightening the clamping screw 39. Pivotally connected to the base member or fence 36 are a plurality of marking-off members 42, 43, 44, 45 and- 46, and pivotally connected to the marking-off member 46 is a further marking-off member 41. All the marking-off members have a slot 48 and by means of pins or studs 49, which work in said slots, said marking-01f members are adjustably connected to the main frame 32, 33, 34. The marking-off members 42 and 43 have rightangled marking-off extension pieces 50 and 5| and the member 45 has a marking-off extension 45a.

The manner in which the marking-off members are anchored to the base member 36 and the frame 32 and their configurations is such that when the base member is set to the angle of the roof, the timbers of which are to be marked-off, all the marking-off members take up a position and present an edge for marking-off the timbers for that particular roof and to which they individually appertain.

In using the instrument the base member or fence is adjusted along the slot 40 to the angle corresponding to the given roof pitch and is locked in this position by means of the clamping screw 39. The cuts of the various roof members are then marked-off by laying the fence along the longitudinal edge of the timber to be cut and marking-01f along an edge of the corresponding marking-oil member for that particular timber.

In Figures '6 to 14 inclusive T represents the timber being marked-01f and a heavy line has been drawn along the edge of the marking-off member which is in use in each of the figures. In Figure 6 a hip rafter plumb cut is being marked-off along the member 42, in Figure 7 a hip rafter foot cut is being marked-off along the member 50, whilst in Figure 8 a jack rafter plumb cut is being marked-off along the member 43. In Figure 9 a jack rafter foot cut is being marked-off along the member I, whilst in Figure 10 a hip rafter top out is being marked-off along the member 44. In Figure 11 a jack rafter top out is being marked-off along the member 45, whilst in Figure 12 a purlin top out is being marked-off along the extension 45a. of the member 45. In Figure 13 a purlin plumb cut or down-cut is being marked-01f along the member 46 whereas in Figure 14 a purlin lip-cut is being marked-oil along the member 41.

In a further construction of an apparatus according to the invention, the straight-edges for marking-off the cuts on the various roof members are formed by the sides of two irregular multilateral-shaped plane members which are pivotally connected to each other at one point so that one member slides over the other, means being provided to secure the two members in any desired relative position. One side of one of the members corresponds to the fence in the previously described construction, and it will be appreciated that by suitably shaping the members, the side edges will form the desired angles with respect to the fenceand that by varying the angular position of one member with respect to the other the angles formed by the sides with respect to the fence will also be varied to give the required angles of cut.

The apparatus may be used in connection with roof timbers for buildings which are out of square in plan as well as those which are squared in plan.

What I claim is:

1. An instrument, for marking-off the angular cuts for the difierent members of a roof, comprising a frame, several marking-off members each having a curvilinear slot defining a characteristic direction of adjustment for its marking-01f member, pivoting and guiding means passing through each slot so as slidably and pivotally to connect its marking-01f member to the frame, a base member having an edge to be set against the timber to be cut and also having a pivotal connection to the frame and means pivotally connecting each marking-01f member separately to said base member.

2. An instrument, for marking-off the angular cuts for the different members of a roof, comprising a frame, several marking-off members each having a curvilinear slot defining a characteristic direction of adjustment for its marking-off member, pivoting and guiding means passing through each slot so as slidably and pivotally to connect its marking-0E member to the frame, a base member having an edge to be set against the timber to be cut and also having a pivotal connection at one of its ends to the frame and a slotted angularly adjustable connection to the frame at its other end, and means pivotally connecting each marking-off member separately to the base member.

3. An instrument as claimed in claim 1 wherein at least one of the marking-off members has a marking-off extension projecting from it at an angle of 4. An instrument as claimed in claim 1 and having at least one additional marking-off member, said additional marking-off member having pivotal connection to one of the other markingoff members and pivotal and slidable connection to the frame.

5. An instrument as claimed in claim 2 and having a scale on the frame against which the angularly adjustable end of the base member is set.

WILLIAM SWIRES.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 996,451 Bragg June 27, 1911 1,293,248 Titanne Feb. 4, 1919 1,553,187 Rutquist Sept. 8, 1925 2,090,835 Gardham Aug. 24, 1937 

